A chimeric gene consisting of a vaccinia virus promoter linked to a cDNA copy of the influenza virus hemagglutinin gene was constructed and inserted into the vaccinia virus genome. Live recombinant virus was isolated and plaque purified. Tissue culture cells infected with the virus synthesized influenza virus hemagglutinin which was glycosylated and transported to the plasma membrane. Following vaccination, experimental animals produced circulating antibodies to the hemagglutinin and cytotoxic T lymphocytes that lysed target cells infected with influenza virus. Hamsters, that received a single intradermal vaccination were protected against influenza respiratory infection.